Global-scale Observations of the Limb and Disk R. Eastes, W. McClintock, M. Lankton, A. Aksnes, D. Anderson, L. Andersson, A. Burns*, S. Budzien, M. Codrescu R. Daniell, K. Dymond, S. England, F. Eparvier, J. Harvey, T. Immel, A. Krywonos, J. Lumpe, A. Richmond, D. Rusch, O. Siegmund, S. Solomon, D. Strickland and T. Woods
Global UV Imaging is the Frontier in Thermosphere-Ionosphere Science Ultraviolet imaging on a global scale is the most effective way to advance thermosphere-ionosphere science Knowledge of temperature and composition on a global scale gives response of thermosphere-ionosphere system to forcing RBSP SDO GOLD The GOLD UV imager complements other existing or planned missions. GOLD COSPAR 08 Page 2
The Thermosphere-Ionosphere (TI) System is an Unusual Laboratory Weak plasma even at 300 km there are 1000 neutrals for every ion Rare in the solar system only occurs in the upper atmospheres of the planets and moons At some heights and locations the ions drive the neutrals at others the neutrals drive the ions Good laboratory for physical and chemical processes The dynamics, thermodynamics and electrodynamics of the TI system are dominated by external forcing processes. GOLD COSPAR 08 Page 3
The Thermosphere-Ionosphere System The thermosphere-ionosphere is controlled by solar and magnetospheric processes, but are the solar high-energy photons more important, or the solar wind - magnetosphere - auroral effects? Solar Ultraviolet and X-rays Forcing from Above Thermosphere- Ionosphere System Solar Wind and Magnetosphere The thermosphere-ionosphere is controlled by atmospheric processes, but are the largescale tidal dynamics more important, or the turbulent and convective processes? Tides and Planetary Waves Forcing from Below Turbulence and Convection GOLD COSPAR 08 Page 4
Forcing from Above Geomagnetic and auroral variations Geomagnetic Storms Magnetospheric Substorms Low-latitude electric field processes Local time dependence of response Solar irradiance variations TIE-GCM Simulation of Temperature (K) at 200 km, 29 October, 2003, 2100 UT Solar Cycle (~11 year) Solar Rotation (~27 day) Active Regions (~days) X-ray Flares (~hours) [Immel et al., 2005] [Sutton et al., 2007] GOLD COSPAR 08 Page 5
Key Science Questions Frame the Mission Temperature (K) 1. A) How do geomagnetic storms alter the temperature and composition structure of the thermosphere; B) How does the lowlatitude, nighttime ionosphere respond to geomagnetic storms; and C) Is the initial state of the thermosphere-ionosphere system a key determinant of geomagnetic storm effects? 2. What is the global-scale response of the thermosphere to solar extreme-ultraviolet variability? 3. Do atmospheric waves and tides have a significant effect on thermospheric temperature structure? 4. Do vertical ion drifts, as manifested in the structure of the equatorial anomaly, affect the occurrence of ionospheric irregularities? GOLD COSPAR 08 Page 6
Comprehensive Investigation Provides Answers to the Science Questions Integrated approach to studying the thermosphereionosphere as a system Full-disk temperature and O/N 2 composition measurements in the Earth s thermosphere Global-scale observations of the ionosphere at night probe the origin of small-scale irregularities Measurements allow separation of temporal and spatial changes GOLD COSPAR 08 Page 7
Management Plan is in Place Team is experienced Partners are committed Instrument has heritage Cost is controlled Schedule matches science goals GOLD COSPAR 08 Page 8
GOLD Configuration Enables Simultaneous Measurements of Composition and Temperature GOLD Summary Volume 40 x 30 x 70 cm 3 Mass 28 kg Average Power 24 W Average Data Rate 2.6 Mbit/sec Two mirror-image instrument channels and a single processor packaged in one housing Each channel operates independently in the nominal GOLD observing mode - Channel A: full disk maps and limb scans with 30 minute cadence (O/N 2, O and N 2 limb emission) - Channel B: sunlit disk maps with 30 minute cadence, interrupted for O 2 occultation measurements (temperature and O 2 limb absorption) A single channel can perform all measurements with reduced cadence or reduced O/N 2 spatial resolution LASP s planetary exploration experience provides the foundation for GOLD s implementation Cassini: Ultraviolet Imaging Spectrograph Messenger: Mercury Atmospheric and Surface Composition Spectrometer GOLD COSPAR 08 Page 9
SES - North American Fleet AMC-18 105 o W C 2022* AMC-2 85 o W C & Ku AMC-8 139 o W C 2016* AMC-7 137 o W C 2015* AMC-10 135 o W C 2019* Brewster Washington AMC-11 131 o W C 2019* AMC-15 105 o W Ku & Ka 2020* AMC-1 103 o W C & Ku 2011* AMC-4 101 o W C & Ku 2014* AMC-3 87 o W C & Ku AMC-16 85 o W Ku & Ka 2020* AMC-9 83 o W C &Ku 2018* AMC-5 79 o W Ku 2010* AMC-6 72 o W C & Ku 2015* Vernon Valley New Jersey South Mountain California Grand Junction Colorado Woodbine Maryland Alexandria Virginia * Manufacturer s Design Life GOLD COSPAR 08 Page 10
Why GOLD? Global UV Imaging is the frontier in thermosphere-ionosphere research. GOLD provides breakthrough imaging of the thermosphereionosphere system. GOLD will analyze the global effects of geomagnetic storms using unprecedented temperature measurements with sophisticated models. GOLD will evaluate the thermosphere-ionosphere response to solar EUV and X-rays, in conjunction with the EUV Variability Experiment (EVE). GOLD will explore ionospheric bubbles, and their connection to the lowlatitude electric fields. GOLD will study the variability of global atmospheric tides and other waves from the unique perspective of geostationary orbit. GOLD and NICE will complement each other to improve the science of both. GOLD COSPAR 08 Page 11